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51.
Tsuji Y Satoh H Itoh N Sekiguchi Y Nagasawa K 《Psychiatry and clinical neurosciences》2000,54(3):276-277
In order to detect rapid eye movements (REM) automatically, the Discrete Wavelet Transform was applied to each 8-s segment of electrooculogram (EOG) data for 30 min of 8 h of normal sleep. The Haar function was used as an analysing wavelet because this function is similar to the REM waveform. By shifting the phase of the analysing wavelet by pi/4 of the function, 96% of REM could be detected. The artifacts caused by body movements could be detected simultaneously by this method. Computing time required for the detection of REM was only 11 s for 30 min EOG data. 相似文献
52.
53.
UV filters with antagonistic action at androgen receptors in the MDA-kb2 cell transcriptional-activation assay. 总被引:4,自引:0,他引:4
Risheng Ma Bea Cotton Walter Lichtensteiger Margret Schlumpf 《Toxicological sciences》2003,74(1):43-50
The fact that certain ultraviolet (UV) filters used in cosmetics display estrogenic activity prompted us to study potential actions on androgen receptors (AR) in the human breast carcinoma cell line MDA-kb2, which expresses functional endogenous AR and glucocorticoid receptors (GR) and is stably transfected with a luciferase reporter plasmid. Dihydrotestosterone (DHT), methyltrienolone (R1881), methyltestosterone, danazol, and androstenedione increased luciferase activity, with EC50 values between 0.11 nM (R1881), 0.14 nM (DHT), and 73.5 nM (androstenedione). DHT-induced luciferase gene expression was inhibited by nonsteroidal antiandrogens, hydroxyflutamide, flutamide, bicalutamide, and vinclozolin. In contrast, the steroidal AR agonist/antagonist cyproterone actetate showed agonistic activity in the absence and presence of DHT, which was not blocked by hydroxyflutamide and thus seems not to be mediated by AR. GR-mediated activation of luciferase by dexamethasone was 100 times less potent than DHT and was not antagonized by hydroxyflutamide. The cell line was used for screening of UV filters, benzophenone-3 (Bp-3), benzophenone-4, 3-benzylidene camphor, 4-methylbenzylidene camphor, butyl-methoxy-dibenzoylmethane, homosalate (HMS), octyl-dimethyl-PABA, and octyl-methoxycinnamate. Two of these, Bp-3 and HMS, antagonized DHT-induced AR activation below cytotoxic concentrations, with IC50 of 5.57 10-6 M (HMS) and 4.98 10-6 M (Bp-3). None of the eight UV filters displayed agonistic activity when tested alone, but high concentrations of Bp-3 induced an increase of luciferase activity in the presence of dexamethasone, which was not blocked by hydroxyflutamide or the estrogen antagonist, ICI 182,780. These data indicate that the UV filters Bp-3 and HMS possess antiandrogenic activity in vitro in addition to estrogenic activity. 相似文献
54.
Objective Discussion of diagnosis, treatment and prognosis of non-palpable TO breast cancer.
Methods Between 1978 and 1997, 9,980 female patients with operable breast cancer were treated surgically, of which 276 were determined
to have TO breast cancer. Most TO breast cancers could be detected promptly with careful examination of presenting symptoms,
such as nipple discharge, local thickening of the breast, nipple erosion, nipple retraction and postmenopausal mastalgia,
while 12 cases were detected by routine mammography of the contralateral breast.
Results All patients were treated surgically and their tissue subjected to histopathological examination. Most cases (73.0%) were
noninvasive or early invasive carcinoma. Axillary lymph nodes metastases were found in 7.69% of 234 mastectomy cases.
Conclusion The survival rate was significantly increased if the tumor was in an early stage. The 5-, 10-, 15-years survival rates were
98.1%, 94.6% and 90.3%, respectively. 相似文献
55.
青钱柳嫩叶中多糖的含量测定 总被引:4,自引:0,他引:4
目的建立青钱柳叶中多糖含量的测定方法.方法采用苯酚-浓硫酸显色法,于490 nm处测吸光度.结果青钱柳嫩叶中多糖含量为0.65 32%;平均回收率99.03%;r=0.9991.结论方法简便、快速,结果准确、可靠,适合多糖的含量测定. 相似文献
56.
目的 :介绍作者所在的实验中心近年来对于黄斑区和近周边视网膜区 (≤ 8°)模糊认知感的研究结果。方法和结果 :先后介绍三个实验。实验一测量了近周边视网膜区的焦深 (即对视网膜离焦的主觉耐受程度 ) ,并将其与黄斑区的反应进行了比较。实验二测量了近周边视网膜区的模糊敏感阈值和模糊辨别阈值。上述两实验结果表明 ,人眼焦深在近周边视网膜区随其与黄斑的距离增大而逐渐升高 ,其值从黄斑区的 0 .89D增加到距黄斑 8度视角离心区的 3.51D。模糊敏感阈值 ,即导致初始模糊认知感的视网膜离焦度 ,也随其与黄斑的距离增大而逐渐升高 ;其值从黄斑区的 0 .85D增加到距黄斑 8度视角离心区的 1 .89D。模糊辨别阈值 ,即在初始模糊认知感的条件下觉察初始模糊程度改变的视网膜离焦度 ,同样亦随其与黄斑的距离增大而逐渐升高 ,其值从黄斑区的 0 .4 5D增加到距黄斑 8度视角离心区的 0 .93D。基于实验一 ,二的结果 ,作者设计了实验三 :通过测量视标大小对焦深的影响以研究近周边视网膜区和黄斑区对模糊认知感的综合效应。结果表明 ,人眼焦深在近周边视网膜区随着视标尺寸的增大而逐渐升高 ,且据其数据分析结果及回归方程斜率的个体差异性 ,可将总体实验对象区分为两个亚组 :即“黄斑主导型”和“黄斑 周边视网膜协 相似文献
57.
人血浆中头孢氨苄浓度高效液相色谱法测定 总被引:3,自引:0,他引:3
目的建立高效液相色谱法测定人血浆中头孢氨苄的浓度。方法采用噻克硝唑为内标,色谱柱为YMC ODS-A C18(150 mm×4.6 mm),流动相为乙腈∶甲醇∶pH 4.5的醋酸盐缓冲液(6∶10∶84),流速为1.0 mL/min,检测波长为260 nm。结果头孢氨苄血清浓度在0.101~32.100μg/mL范围内具有良好线性关系,最低定量限为0.101μg/mL,方法回收率为97.5%~103.0%,日内、日间相对标准差均<7%。结论高效液相色谱法简便、准确、灵敏,适用于头孢氨苄血药浓度监测和药代动力学研究。 相似文献
58.
Mahesh Chandra Hedge Panduranga M. Kamath Suja Shreedharan Naveen Kumar Dannana Ravikumar M. Raju 《Indian journal of otolaryngology and head and neck surgery》2006,58(1):31-34
The efficacy of supravital staining in the detection of malignancies in oro and oropharyngeal lesions and its role in the
detection of malignant changes in premalignant lesions were studied. This prospective study comprises 90 cases of clinically
suspicious lesions and it was done over a period of 3 years. Most of the patients had multiple risk factors for the development
of malignancy. All underwent staining with a modified solution of 1% toluidine blue (TB). In our study the overall sensitivity
was 97.29% and the specificity was 62.5%. 相似文献
59.
60.
目的:寻求一种鉴定天花粉与其混淆品长萼瓜蒌的有效方法。方法:采用天花粉双边栝楼根以及瓜氨酸作为对照物质,与长萼瓜蒌根同时进行紫外光谱扫描。结果:紫外光谱显示,长萼瓜蒌的水和乙醇溶液在272nm波长处均有最大吸收,而天花粉及瓜氯酸均无此光谱特征,可资鉴别。结论:用紫外光谱法鉴定天花粉与长萼瓜蒌,方法简便可行,结果准确可靠。 相似文献